WASHINGTON — No Democratic attorney general in a state that prohibits same-sex couples from marrying has signed onto a legal filing asking the Supreme Court to uphold California’s constitutional ban on gay marriage.

No Republican attorney general is asking the high court to rule in favor of marriage equality.

The Republican leadership in the House of Representatives, supported by 10 GOP senators, is spearheading the defense of the federal law that prevents legally married gay couples from collecting a range of federal benefits otherwise available to married couples.

Some 212 Democrats and independents in Congress want part of the federal Defense of Marriage Act overturned. That includes 24 who initially voted for it.

A continuing distinct partisan divide is present in the gay marriage cases at the Supreme Court, set for arguments March 26-27, even though a brief on behalf of more than 100 prominent Republicans calls for marriage equality. The split is most apparent in legal briefs filed with the court by state attorneys general.

All 21 attorneys general who have signed legal briefs or letters urging the court to uphold California’s ban on same-sex marriage are Republican.

The result of the federal appeals court ruling striking down California’s ban, known as Proposition 8, “is disintegration of perhaps the most fundamental and revered cultural institution of American life: marriage as we know it,” the Republicans said. The states represented on the briefs mostly are reliably Republican and chose GOP nominee Mitt Romney over President Barack Obama in November.

But also are included are four states won by Obama — Colorado, Michigan, Virginia and Wisconsin.

Another 14 attorneys general who are asking for the opposite outcome are Democrats, including those from the nine states that allow gay weddings. Also among those Democrats are California’s Kamala Harris and Ellen Rosenblum of Oregon, which has a constitutional prohibition on same-sex weddings. Obama won all 14 states.

Removing barriers and promoting the equality of spouses has strengthened the institution of marriage, the Democratic attorneys general said. “Over the past decade, this evolution has been affirmed as same-sex couples have been permitted to marry. Against that history of greater inclusion and equality, Proposition 8 singles out same-sex couples and excludes them from the opportunity to marry,” the Democrats said.